The invention relates to an apparatus for conveyance, in particular, to an apparatus for conveyance which is preferred for use in the manufacture of semiconductor chips.
A semiconductor manufacturing system generally comprises a bonder, which conveys semiconductor chips, and a feeder, which is mechanically coupled to and coordinated with the bonder for coordinated motion therewith for feeding lead frames.
Reference is now made to FIGS. 1 to 9 to describe a bonder 100 and a feeder 140 used in the prior art. In the description to follow, the lateral direction of bonder 100 and feeder 140 is defined as the X-axis direction, while the fore-and-aft direction thereof is defined as the Y-axis direction.
The bonder 100 will be described first with reference to FIGS. 1 to 7. FIG. 1 is a top view, FIG. 2 a front view, FIG. 3 is a left-hand side elevation and FIG. 4 a right-hand side elevation of the bonder.
Referring to FIG. 1, the lower portion as viewed in FIG. 1 represents a front portion of the bonder 100 while the upper portion as viewed in FIG. 1 represents a rear portion of the bonder 100. The bonder 100 includes a box-shaped first base 101 and a drive motor 102 fixed to the first base 101. The motor 102 has an output shaft on which a disc cam 103 and a splined shaft 104 are mounted. A cylindrical cam 105 is mounted on the splined shaft 104 in an axially movable manner and includes a helical cam groove 105a. 
Referring to FIG. 4, an arm 107 is connected to the cylindrical cam 105 through a cam follower 108, which is fixed to the arm 107 and is pressed into the cam groove 105a of the cylindrical cam 105. A horizontal guide 106 is mounted on the first base 101 for guiding movement of the arm 107. When the drive motor 102 is set in motion to rotate the cylindrical cam 105, the arm 107 is reciprocated by the cam follower 108 in the X-axis direction.
Referring to FIG. 3, a plurality of vertical guides 109 are mounted on the lateral surface of the first base 101, and a plate 110 connected to the vertical guides 109 is allowed to move in the vertical direction, or Z-axis direction. A rail 111 extending along the Y-axis direction is secured to the bottom of the plate 110. As shown in FIG. 2, a cam follower 113 is secured to the top of the plate 110 through a connecting plate 112. The cam follower 113 contacts the top of the disc cam 103. When the drive motor 102 rotates the disc cam 103, the plate 110 and the rail 111 are reciprocated by the cam follower 113 in the vertical direction.
Returning to FIG. 3, the arm 107 has a vertical guide 116 at one end, and a fastening member 115 fastens the vertical guide 116 and the rail 111. The vertical guide 116 guides movement of the fastening member 115 in the vertical direction and guides movement of the fastening member 115 in the Y-axis direction. A bonding head or pickup head 114 is fixed to the fastening member 115. When the drive motor 102 drives both the cylindrical cam 105 and the disc cam 103 for rotation simultaneously, the arm 107 moves in the Y-axis direction while the rail 111 moves in the vertical, or X-axis, direction. Accordingly, the pickup head 114 moves in the Y-axis direction in accordance with the movement of the arm 107 and moves in the vertical direction in accordance with the movement of the rail 111. In this manner, the pickup head 114 performs a series of mounting operations through these movements in the both directions.
Returning to FIG. 1, an inching motor 117 is fixed to the lateral surface of the first base 101 at a location below the drive motor 102. The inching motor 117 has an output shaft connected to a ball screw 118, which is threaded to a linear bushing 119. The linear bushing 119 slides along a shaft 120, which extends in the Y-axis direction. The linear bushing 119 carries a cam follower 121 (see FIG. 2), which bears against a disc portion 122, which is formed at one end of the cylindrical cam 105. When the motor 117 drives the ball screw 118, the linear bushing 119 and the cam follower 121 move in the Y-axis direction. As the cam follower 121 moves, the cylindrical cam 105 moves along the splined shaft 104. The movement of the cylindrical cam 105 is transmitted through the cam follower 121 to cause an inching motion of the arm 107 and the pickup head 114.
As shown in FIG. 2, a second base 124 is located below and supports the first base 101. Above the second base 124, a plurality of shafts 125 extend in the X-axis direction. A linear bushing 123 slides along these shafts 125. The first base 101 is movable in the X-axis direction along the shafts 125.
Another inching motor 126 is mounted on the second base 124 and has an output shaft having threads for engagement with the first base 101. When the motor 126 drives the threaded shaft, the first base 101 is moved in the X-axis direction. As the first base 101 moves, the pickup head 114 undergoes an inching motion in the X-axis direction.
Referring to FIGS. 5 to 7, the construction of the pickup head 114 will be described. FIG. 5 is a right-hand side elevation, FIG. 6 a top view and FIG. 7 a front view of the pickup head 114.
Referring to FIG. 5, the pickup head 114 is provided with a leveling regulating mechanism for adjusting the lower surface of a collet 127, which is used to hold a semiconductor chip in a horizontal plane. The pickup head 114 is constructed to a high structural rigidity with first to fourth metallic bodies 128 to 131. The first body 128 is connected to a second body 129, which is then connected to a third body 130, which is, in turn, connected to the fourth body 131. In each instance, the connection takes place by way of a screw 132, the tightening of which may be regulated to bring the lower surface of the collet 127 into a horizontal plane. The first body 128 is pivotal about a fulcrum A relative to the second body 129. As shown in FIG. 6, the second body 129 is pivotal about a fulcrum B relative to the third body 130. As shown in FIG. 7, the third body 130 is pivotal about a fulcrum C relative to the fourth body 131.
The bonder 100 causes the pickup head 114 to perform a series of normal mounting operations when the drive motor 102 is set in motion. The pickup head 114 undergoes an inching motion when the inching motors 117, 126 are set in motion, thus performing a fine adjustment of its position. Specifically, the position of the pickup head 114 when it picks up a semiconductor chip or when it loads a semiconductor chip on a lead frame is finely adjusted.
Referring now to FIGS. 8 and 9, the feeder 140 will be described. FIG. 8 is a side elevation of the feeder 140, and FIG. 9 is a plan view of an essential part of the feeder 140.
Referring to FIG. 8, the feeder 140 includes an actuator 133 extending in the X-axis direction and a carriage 134 mounted on top of the actuator 133. In response to the actuation of the actuator 133, the carriage 134 moves in the X-axis direction. The carriage 134 includes a damper 135 and an air cylinder 136 which drives the damper 135. Thus, the damper 135 is moved in the Y-axis direction when the air cylinder 136, is operated. The carriage 134 is fixed to a pipe bearer 137 formed by a plurality of interconnected sleeves and containing a piping, not shown, connected to the air cylinder 136.
As shown in FIG. 9, the air cylinder 136 has a rod 136a, which is connected to a linkage 138, which is, in turn, connected to an upper damper 135a (see FIG.8) of the damper 135. The upper damper 135a is rotatable about a rotary mechanism 139. When the rod 136a is driven, the upper damper 135a assumes a pivoted position as shown in phantom lines in FIG. 8, thus opening the damper 135. In this manner, the damper 135 is opened and closed in response to a movement of the air cylinder 136.
In operation, the damper 135 carries a lead frame, not shown, and the carriage 134 brings the lead frame to a given position. The bonder 100 mounts a semiconductor chip on the lead frame which is brought to the given position.
However, the speed with which the pickup head 114 of the bonder 100 is moved or the speed of conveyance cannot be increased for the following reasons:
(1) the arm 107 carries, at its front end, the vertical guide 116, which adds to the weight of the arm 107;
(2) the pickup head 144 is fixed on the fastening member 115, which connects the vertical guide 116 to the rail 111, thus increasing the weight of the movable assembly;
(3) when the pickup head 114 is to be moved in the Y-axis direction during a normal mounting operation, the arm 107 slides along the horizontal guide 106 while the fastening member 115 slides along the rail 111, thus presenting an increased frictional resistance;
(4) when the pickup head 114 is moved in the Y-axis direction by the inching motion, the linear bushing 119 slides along the shaft 120 while the cylindrical cam 105 slides along the splined shaft 104, thus presenting an increased frictional resistance;
(5) when the pickup head 114 is moved vertically during the normal mounting operation, the plate 110 slides along the vertical guide 109 while the fastening member 115 slides along the vertical guide 116, again presenting an increased frictional resistance; and
(6) the first to the fourth bodies 128-131 are used for the pickup head 114 to allow the lower surface of the collet 127 to be brought into a horizontal plane. The high rigidity required for each of the bodies 128-131 necessarily increases their weight and adds to the weight of the pickup head 114.
On the other hand, the feeder 140 includes the carriage 134, which is provided with the air cylinder 136 to serve as a drive source for directly driving the damper 135, thus adding to the weight of the carriage 134. Consequently, the speed with which the damper 135 is moved or the speed of conveyance for the lead frames cannot be increased.
It is an object of the invention to provide an apparatus for conveyance and a semiconductor manufacturing system that permit an increase in the speed of conveyance.
To achieve the above objective, the present invention provides an apparatus for conveyance of a semiconductor chip, comprising: an arm for conveying a semiconductor chip; a holder member on the arm for holding the semiconductor chip; a first transmission mechanism for producing power acting in a first direction; an interconnection mechanism for interconnecting the first transmission mechanism and the arm for causing movement of the arm in the first direction; and a second transmission mechanism connected to the arm for moving the arm in a second direction which is substantially orthogonal to the first direction, wherein the interconnection mechanism is configured to permit movement of the arm with respect to the first transmission mechanism in the second direction and to transmit the power from the first transmission mechanism to the arm.
The present invention further provides a bonding head for conveying a semiconductor chip, comprising: a body; a collet supported by the body for holding a semiconductor chip; a pipe shaft for supporting the collet, wherein the body includes a through-opening extending vertically, for receiving the pipe shaft; and a regulation mechanism mounted on the body for regulating inclination of the collet, wherein the regulation mechanism including: a bearing received within the through-opening in a tiltable manner for supporting the pipe shaft; a support formed at the lower end of the through-opening for supporting part of the bearing; and a plurality of holding members for applying force to the bearing in mutually different directions at locations above the support for positioning the bearing.
The present invention provides a apparatus for conveyance comprising: a base extending along a particular conveying direction; a carriage that is movable on the base in the conveying direction; a first drive source for moving the carriage; a damper mounted on the carriage, the damper being and adapted to be selectively opened and closed for holding an article to be conveyed; a resilient member for urging the damper in a direction to close it; a second drive source on the base; and a transmission member for transmitting power from the second drive source to the resilient member to open the damper against the force the resilient member.
Other aspects and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example, the principles of the invention.